If the plunger does not snap into locking position this component is damaged and needs to be.
My fuel door wont lock on my 2007 audi a4.
Changed door control module via ebay all ok now.
Make sure the electrical harness is connected.
If you open the fuel door and lock the car the pin extends.
Window sometimes didn t work.
Audi a4 b7 b8 door lock problems diagnostic guide door lock problems diagnostic guide experiencing problems un locking your doors.
If a fresh battery fixes the problem consider yourself lucky.
As the door latched cables wires seemed fine.
I had a door on my 2007 b7 a4 which didn t lock.
As you push it in you can feel the gears turning.
My diagnosis was the door control module.
Another bug bear are the wires inside socket in the door between the pillar door.
You can push it in with your finger but it takes force.
Door lock problems diagnostic guide.
If you notice that despite being not terribly far away from the car it is not reacting to the queue to lock unlock the vehicle then it might be time to replace the fob battery.
Check the battery of the fob try to lock and unlock the door from varying distances.
This article applies to the audi a4 b7 b8 2005 2015.
The first and most obvious thing to check is your key fob battery.
The electrical connection for the fuel door button on some audi s isn t secured well.
If t0m3k found that the pin went in with little pressure i suspect the gears in the motor are not functioning properly.
With the fuel door open as the image displays press the plunger down to lock into position.
On the side of the gas door remove the panel from the trunk to locate the electrical harness.
If not also check your battery s voltage to make sure it s reading 12 volts with the ignition off and 14 volts with the ignition on and the alternator running.